Automatic floor cleaning machines are designed to clean hard floor surfaces. Typically, the automatic floor cleaner applies detergent solution to an area of the floor, scrubs the floor with the detergent solution, and vacuums the dirty or spent wash water off the floor area. The floor cleaning machine has a compartment for the clean detergent solution, and a compartment for the dirty detergent solution. During use, the detergent solution is progressively transferred from the clean solution compartment to the dirty or spent solution compartment.
The operator makes the detergent solution by adding a certain amount of concentrated liquid detergent to a certain quantity of clean water. The concentration of the resulting detergent solution may be rather imprecise, in that it depends merely upon the ratio of concentrate detergent solution to water. If too little detergent solution is added, then there may be inadequate cleaning of the floor. If too much detergent solution is added, then an undesirable residue, excessive foaming, and waste of the detergent may result.
With conventional floor scrubbers, the concentration of the detergent solution is fixed once the solution has been made. However, the optimum detergent concentration will vary according to the type and amount of soil on the floor, the type of floor cleaning machine, the type of cleaning chemical being dispensed, the type of surface being cleaned, the temperature of the solvent, the degree of mechanical action applied to the floor being cleaned, and the volume of cleaning solution being produced. With known designs, the only variables available to the operator in adjusting the cleaning efficiency of the unit are: (1) the dispensing rate of the detergent solution, (2) the linear velocity of the machine, and 3) the ability to make repetitive passes over the floor area. The former variable is the rate of the detergent solution flowing onto the scrubbing brush. As a result, the operator's ability to control the detergent action of the machine is somewhat limited.
With conventional floor cleaners, it is also relatively difficult for the operator to rinse the floor with clear water, because there is no capability for clear water to be conveniently dispensed from the floor scrubber. In order to rinse the floor, the user must assemble a separate hose assembly from a nearby water supply point. This is an inconvenient and time-consuming process, especially if the water source is remote from the floor area that is being rinsed. It is possible to dispense water through the floor scrubber if the detergent solution from the solution tank is completely drained and the tank is then filled with fresh water. However, the solution tank contains detergent residue, and this process would be time-consuming and difficult.
The present invention addresses these and many other problems associated with currently available floor cleaning systems.